US3954602A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for cleaning used oils
Assignee: Parisiene des Lubrifiants Nationaux
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Filing: 1974-02-20
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Granted: 1976-05-04
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Expires: 1994-02-20
Abstract
Abstract A process for cleaning a used oil, in particular engine oil and industrial lubricating oil. The process comprises heat treating the used oil in a heat treatment zone at a temperature of 325°-400°C at a pressure of 1-6 bars for a period of at least 15 minutes, continuously withdrawing a first part of the treated oil from the heat treatment zone, re-heating said first part of the oil and recycling the re-heated first part of the oil through the heat treatment zone, subjecting the remainder of the heat treated oil from the heat treatment zone to a treatment for separating out the sedimentary residues from the heat treated oil. The sedimentary residues are incinerated in the re-heating furnace for re-heating said first part. A system is described for carrying out the process.
Inventors
- 👤 Andre Troesch
- 👤 Fernand Cleron
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:40
CPC Classifications
C; C10; C10M; C10M175/00; C10M175/0025
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
124 words
A process for cleaning used engine oils and industrial lubricating oils, comprising, (a) heat treating the used oil in a heat treatment zone at a temperature of 352°-400°C at a pressure of 1-6 bars for a period of at least 15 minutes, continuously withdrawing treated oil from said heat treatment zone, (b) re-heating a first portion of said treated oil to the treatment temperature and recycling the re-heated first portion of said treated oil to said heat treatment zone at a re-cycling rate in the range of 5 to 20, (c) separating the sedimentary residues from a second portion of said heat treated oil and (d) burning said residues from step (c) for re-heating said first portion of said treated oil in step (b).
Claim 2
Dependent Claim
124 words
A process for cleaning used engine oils and industrial lubricating oils, comprising, (a) heat treating the used oil in a heat treatment zone at a temperature of 352°-400°C at a pressure of 1-6 bars for a period of at least 15 minutes, continuously withdrawing treated oil from said heat treatment zone, (b) re-heating a first portion of said treated oil to the treatment temperature and recycling the re-heated first portion of said treated oil to said heat treatment zone at a re-cycling rate in the range of 5 to 20, (c) separating the sedimentary residues from a second portion of said heat treated oil and (d) burning said residues from step (c) for re-heating said first portion of said treated oil in step (b).
Claim 3
Dependent Claim
44 words
A process as claimed in claim 1, wherein the separation of said residues is carried out by passing said second portion of said treated oil through a cellulosic filtration adjuvant, the mixture of said residues and said filtration adjuvant being burned in step (d).
Claim 4
Dependent Claim
18 words
A process as claimed in claim 1, wherein the separation of the residues is carried out by centrifugation.
Claim 5
Dependent Claim
41 words
A process as claimed in claim 1, wherein the heat treatment temperature is between 350° and 380°C, said pressure is between 2 and 5 bars and the total time of stay of the oil in the treatment zone is 15-30 minutes.
Claim 6
Dependent Claim
60 words
A process as claimed in claim 1, further comprising collecting from said heat treatment zone a light fraction which distills, separating said fraction into a light oil fraction, which is returned at least partly to said heat treatment zone, and an aqueous effluent fraction and mixing said aqueous effluent fraction with the sedimentary residues for said burning in step (d).
Claim 7
Dependent Claim
147 words
A process for cleaning used engine oils and industrial lubricating oils, comprising (a) heat treating the used oil in a heat treatment zone at a temperature of 325°-400°C at a pressure of 1-6 bars for a period of at least 15 minutes, continuously withdrawing a first portion of the heat treated oil from the heat treatment zone, (b) re-heating said first portion of the oil to said treatment temperature and recycling the re-heated first portion of the oil through said heat treatment zone at a re-cycling rate in the range of 5 to 20, (c) separating the sedimentary residues from a second portion of the heat treated oil by passing said second portion of said treated oil through wood dust and (d) burning the mixture of said residues and said wood dust from step (c) for re-heating said first portion of said treated oil in step (b).
Claim 8
Dependent Claim
147 words
A process for cleaning used engine oils and industrial lubricating oils, comprising (a) heat treating the used oil in a heat treatment zone at a temperature of 325°-400°C at a pressure of 1-6 bars for a period of at least 15 minutes, continuously withdrawing a first portion of the heat treated oil from the heat treatment zone, (b) re-heating said first portion of the oil to said treatment temperature and recycling the re-heated first portion of the oil through said heat treatment zone at a re-cycling rate in the range of 5 to 20, (c) separating the sedimentary residues from a second portion of the heat treated oil by passing said second portion of said treated oil through wood dust and (d) burning the mixture of said residues and said wood dust from step (c) for re-heating said first portion of said treated oil in step (b).
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-05-04 | 1979-11-03 | 1980-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-04 | 1983-11-03 | 1984-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-04 | 1987-11-03 | 1988-05-04 | $7700.00 | Window Closed / Lapsed |